Structuring white rice with gellan gum reduces the glycemic response in healthy humans

White rice has a high glycemic index and its consumption has been linked to an increased risk of developing type-2 diabetes mellitus, increased diabetes associated complications and obesity. In recent in vitro studies we have shown that addition of food hydrocolloids, such as low acyl gellan gum (LAGG), when cooking white rice potentially modifies starch digestion kinetics. The impact in vivo remains to be investigated. We aimed to determine the effect of adding LAGG to white rice on postprandial glycemic, gastrointestinal and appetitive responses in humans. Following LAGG in vitro characterisation, 12 healthy adults participated in a randomised, controlled, crossover study. They consumed isoenergetic meals of jasmine white rice (232 kcal) cooked with (Rice + LAGG) and without (Rice control) 3 % w/dry rice w LAGG. Blood glucose, intragastric meal appearance, meal volume and appetite were assessed serially for 2 h. The incremental area under the curve over two hours (iAUC2h) for blood glucose for the Rice + LAGG meal (93 +/- 16 mmol/L<middle dot>min) was significantly lower than that for the Rice control meal (160 +/- 18 mmol/L<middle dot>min), P=0.0007. Blood glucose rose postprandially to a peak at T=30 min, with the Rice control meal peak (7.3 +/- 0.2 mmol/L) significantly higher than that for the Rice + LAGG meal (6.5 +/- 0.2 mmol/L), P < 0.01. MRI images showed that for Rice + LAGG there were multiple rice boluses persisting intragastrically throughout the digestion time. There were no significant differences in appetite between meals. The addition of LAGG to the cooking process was effective in reducing postprandial blood glucose responses in healthy humans. If confirmed, this could potentially provide a simple and relatively inexpensive intervention to reduce the post prandial glycemic response to white rice.